Industrial cutting and grinding machinery in a broad range of forms is designed to operate in conjunction with fluid cooling systems wherein a liquid, i.e. mineral-free water, plus a soluble or emulsified oil is continuously circulated over work surfaces and the like to carry off thermal energy generated in machine operation. As the coolant is circulated within the machine environment, it gradually will become contaminated with hydrocarbon lubricants which migrate into the coolant flow path. Should this hydrocarbon contamination not be corrected, cooling efficiency of the machinery diminishes, smoke is produced and eventual clogging of the system with concomitant shutdown will ensue.
Generally such products as straw or cotton or various mixed cellulosic materials are used on oil spills for the absorbent medium, the latter having a dusty character found to be objectionable. These conventional oil adsorbing materials are not ideal inasmuch as with their use the resultant weight-to-weight ratio of adsorbent material to oil picked up is less than one-to-ten in most instances. Granulated polystyrene foam has been used as an absorber of oil and like hydrocarbons due to the oil affinity of its surface achieved by virtue of its hydrocarbon content. However, polystyrene materials must be "blown" or produced under carefully controlled factory conditions, generally a methylchloride or the gaseous blowing agent being used and high temperature heat sources being required for carrying out the reactions involved. Thus, such materials are too costly for most applications.
Over the recent past, as the transportation of petroleum products by sea has greatly expanded, significant oil spills have been encountered. When these spills migrate toward land, it has been necessary for governmental agencies and affected industy to carry out clean-up procedures, all such currently envisioned procedures being of questionable effectiveness. Usually, elongate floating containers fashioned of inexpensive oil adsorbents within a perforate retainer or casing are formed as adsorbant booms in a line and floated against the oil slick to gradually confine and collect it. Typical adsorbent materials used within these devices are essentially the same as described above in connection with industrial machinery utilization and, in addition to having the noted relatively low oil pick-up ratio, tend to adsorb water and sink after a limited period of use. Of course the costs encountered in transporting the very light adsorbing materials to the site of an oil collecting activity are somewhat prohibitive in view of the low density of the materials involved.